Annealing kiln cooling air control system based on DCS centralized control

Abstract

The utility model discloses an annealing kiln cooling air control system based on DCS (Distributed Control System) centralized control, which comprises an RET area fan M1 air outlet pipeline and a natural cold air pipeline which are both connected to a mixed air pipeline, the mixed air pipeline is used for mixing the natural cold air of the natural cold air pipeline and the extracted hot air in the annealing kiln to obtain mixed air, and the mixed air is connected to the air pipes at the upper part and the lower part of the RET area glass belt; regulating valves at the RET area air pipes are arranged at the positions, on the upper portion and the lower portion of the RET area glass tape, of all the area air pipes. The output end of the temperature measuring element is connected to the input end of the DCS control module; the output end of the DCS control module is connected to an RET area fan M1 through an RET area frequency converter; the DCS control module is connected to the natural cold air control valve and the control end of the RET area air pipe adjusting valve. The defects existing in manual control over cooling air of the annealing kiln are overcome, centralized automatic control is conducted through a DCS, meanwhile, control parameters are recorded and stored, and follow-up inquiry and tracing are facilitated.

Description

Technical Field

[0001] The utility model relates to the field of glass annealing furnaces, in particular to a cooling air control system for annealing furnaces based on DCS centralized control. Background Art

[0002] Glass annealing furnace is a device for improving glass stress. It directly affects the glass yield and subsequent processing of glass, and plays an important role in glass production. The type, performance, production scale and quality of glass products determine the annealing process of the annealing furnace. For example, a method for isothermal drop rate cooling in the forced convection zone of a glass annealing furnace with patent application number 201410286520.3 allows a glass ribbon carrying glass thereon to pass through the forced convection zone of the annealing furnace, and air-cools the glass in the forced convection zone while moving the glass ribbon. Different air volumes are formed according to the temperature of the glass to air-cool the glass, so that the glass is cooled at an isothermal drop rate during the movement.

[0003] At present, the current status of the cooling air control circuits in the RET zone (circulating hot air cooling zone) and F zone (direct cooling zone) of the photovoltaic glass annealing furnace is as follows:

[0004] RET zone: hot air circulation cooling zone, using hot air with adjustable temperature to force direct convection cooling of the glass ribbon. Using the hot air in the kiln, with a certain amount of natural room temperature air, the fan will re-blow the hot air at a certain temperature onto the glass ribbon, and use its forced convection to quickly cool the glass ribbon. The photovoltaic glass annealing furnace is divided into five or four zones horizontally according to the width of the glass ribbon (five wide lines: west plate, west middle plate, middle plate, east middle plate, east plate; four narrow lines: west plate, west middle plate, east middle plate, east plate), each zone has several groups of flat air nozzles, and each zone is manually controlled by manual valves. There are long air nozzles (under the plate) that are not divided horizontally at the bottom of the glass ribbon. The cooling air is sent into the cooling air duct from the two sides, and the air volume is also manually controlled by manual valves.

[0005] F zone: cold air forced convection cooling zone. The structure of F zone is basically the same as RET zone. In this zone, the fan directly extracts the natural cold air from the room and blows it to the surface of the glass belt without mixing the circulating hot air. Like RET zone, the air volume at the outlet of F zone is also adjusted by manual valve.

[0006] In the prior art, the air volume adjustment of the RET zone and the F zone of the annealing furnace is performed by manual valves. The control by manual valves leads to the defects of cumbersome operation and poor safety, specifically:

[0007] 1. Complicated operation: In the large-scale production of photovoltaic glass, in order to meet the production needs, the air valves in the RET and F zones of the annealing furnace need to be adjusted frequently, which requires frequent operation by personnel and has high labor intensity, making it unsuitable for large-scale production.

[0008] 2. Poor safety: When operating the manual valve, personnel need to be close to the annealing kiln. The temperature around the annealing kiln is high, the airflow is turbulent, and production abnormalities such as glass explosion may occur, posing certain safety hazards.

[0009] 3. Low precision: When the photovoltaic glass annealing kiln processes large-tonnage photovoltaic glass sheets, it has high requirements for the adjustment accuracy of parameters such as flow, temperature and pressure. The control accuracy of manual valves is affected by manual operation and has relatively low accuracy.

[0010] Therefore, the existing technology of using manual control to control the cooling air of the annealing furnace cannot meet the requirements of glass production for safety, reliability, and high precision. At the same time, the wind control system of the annealing furnace in the existing technology is manually controlled, and the parameters in the control process cannot be saved and recorded in time, and the data parameters before and after each air valve adjustment cannot be efficiently and completely recorded. There is a lack of a series of data support when analyzing and studying the performance of the product and the subsequent processing effects of the original glass sheet (such as cold end cutting, tempering treatment, etc.). Utility Model Content

[0011] The utility model aims to overcome the deficiencies of the prior art and provide an annealing kiln cooling air control system based on DCS centralized control, which is used to solve the defects of manual control of annealing kiln cooling air, adopts DCS for centralized automatic control, and records and saves control parameters at the same time, which is convenient for subsequent query and tracing.

[0012] In order to achieve the above-mentioned purpose, the technical solution adopted by the present invention is: a cooling air control system for an annealing kiln based on DCS centralized control, comprising a DCS control module, a RET zone fan M1, a natural cooling air control valve, a RET zone frequency converter, and a temperature measuring element, wherein the RET zone fan M1 is used to extract hot air in the annealing kiln, and the RET zone fan M1 air outlet duct and the natural cooling air duct are both connected to a mixed air duct, and the mixed air duct is used to mix the natural cooling air of the natural cooling air duct and the extracted hot air in the annealing kiln to obtain a mixed air and connect it to The air ducts of each zone at the upper and lower parts of the glass belt of the RET zone; the air ducts of each zone at the upper and lower parts of the glass belt of the RET zone are provided with regulating valves at the RET zone air ducts; the temperature measuring element is used to detect the temperature data of the mixed air, and its output end is connected to the input end of the DCS control module; the output end of the DCS control module is connected to the RET zone fan M1 via the RET zone frequency converter, and is used to control the fan operating frequency of the RET zone fan M1; the DCS control module is respectively connected to the control ends of the natural cooling air control valve and the regulating valve at the RET zone air duct.

[0013] The control system also includes a fan M2 in zone F, a manual butterfly valve, and a frequency converter in zone F. The air inlet duct of natural cold air in zone F is connected to the air inlet of the fan M2 in zone F, and a manual butterfly valve is arranged on the air inlet duct; the air outlet of the fan M2 in zone F is respectively connected to the cooling air ducts corresponding to the upper and lower parts of the glass ribbon in zone F through air ducts, and the cooling air ducts corresponding to the upper and lower parts of the glass ribbon in zone F are provided with air duct regulating valves in zone F for controlling the air volume of the air ducts; the DCS control module is connected to the fan M2 in zone F through the frequency converter in zone F, and is used to control the working frequency of the fan M2 in zone F; the DCS control module is respectively connected to each air duct regulating valve in zone F.

[0014] The regulating valves at the RET zone air duct and the F zone air duct regulating valves are both pneumatic regulating valves, and are controlled by the regulating signals sent by the DCS control module.

[0015] The regulating valves at the RET zone air ducts and the regulating valves at the F zone air ducts are both equipped with local valve position display modules.

[0016] An air volume sensor is provided at the air inlet of the mixed air duct and / or the fan M2 in zone F for collecting actual air volume signals, and its output end is connected to the input end of the DCS control module.

[0017] The DCS control module is integrated into the DCS system for glass production control.

[0018] The DCS control module is connected to a memory, and the memory is used to store event information corresponding to cooling air control.

[0019] The memory adopts EEPROM.

[0020] The DCS control module is connected to an alarm device for issuing an alarm for abnormalities in the cooling air control system of the annealing furnace.

[0021] The utility model has the advantages of solving the defects of manually controlling the cooling air of the annealing kiln, adopting DCS for centralized automatic control, and recording and saving the control parameters at the same time, which is convenient for subsequent inquiry and tracing. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The following is a brief description of the contents expressed in the drawings of the present invention and the symbols in the drawings:

[0023] Figure 1 This is the principle diagram of the control system of the utility model;

[0024] Figure 2 This is a control diagram of the RET area of ​​the utility model

[0025] Figure 3 This is a control schematic diagram of the F zone of the utility model. DETAILED DESCRIPTION

[0026] The specific implementation of the present invention will be further explained in detail below by describing the optimal embodiment with reference to the accompanying drawings.

[0027] The technical solution of this embodiment aims at the defects of manual control in the prior art, and connects the annealing kiln wind control to the DCS system for centralized control, which can improve the automation and reliability of the control, and can also record the parameters in the control process, which is convenient for subsequent tracing and data search. The specific solution is as follows:

[0028] like Figure 1 As shown, a cooling air control system for an annealing furnace based on DCS centralized control includes a DCS control module, a RET zone fan M1, a natural cooling air control valve, a RET zone frequency converter, and a temperature measuring element, wherein the RET zone fan M1 is used to extract hot air and natural cooling air in the annealing furnace, and the RET zone fan M1 air outlet duct is connected to the mixed air duct, and the mixed air duct is used to mix the natural cooling air of the natural cooling air duct and the extracted hot air in the annealing furnace to obtain mixed air and connect it to each zone air duct at the upper and lower parts of the RET zone glass belt; each zone air duct at the upper and lower parts of the RET zone glass belt is provided with a RET zone air duct regulating valve; the temperature measuring element is used to detect the temperature data of the mixed air, and its output end is connected to the input end of the DCS control module; the output end of the DCS control module is connected to the RET zone fan M1 via the RET zone frequency converter, and is used to control the fan operating frequency of the RET zone fan M1; the DCS control module is respectively connected to the control ends of the natural cooling air control valve and the RET zone air duct regulating valve.

[0029] When the wind control is performed in the RET area, its working principle is as follows: the DCS control module can control the operation of the fan M1 in the RET area through the frequency converter to realize the hot air volume in the annealing furnace extracted by the fan M1. At the same time, the DCS control module can control the air volume of the natural wind by controlling the natural cold wind control valve. The natural wind is also extracted through the fan. The DCS control module adjusts the cooling air intake by controlling the opening of the natural cold wind control valve, thereby realizing the air volume and temperature of the mixed air. The hot and cold mixed air is sent to the air ducts of the upper and lower areas of the glass belt corresponding to the RET area. These air ducts are used to blow and cool the glass belt. The air ducts in each area are provided with air duct regulating valves. The DCS control module is used to control these air duct regulating valves to control the wind blowing control of the glass belt. At the same time, a temperature measuring element for detecting the temperature of the mixed air is provided, which adopts a temperature sensor to obtain the temperature signal of the mixed air. The output end of the temperature measuring element is connected to the DCS control module, which is used to send the temperature of the mixed air to the DCS control module. The DCS control module controls the opening size of the natural cooling air control valve and the speed and frequency of the corresponding fan based on the temperature signal of the mixed air.

[0030] The control system of zone F includes a fan M2 in zone F, a manual butterfly valve, and a frequency converter in zone F. The air inlet duct of natural cooling air in zone F is connected to the air inlet of the fan M2 in zone F, and a manual butterfly valve is arranged on the air inlet duct; the air outlet of the fan M2 in zone F is respectively connected to the cooling air ducts corresponding to the upper and lower parts of the glass ribbon in zone F through air ducts, and the cooling air ducts corresponding to the upper and lower parts of the glass ribbon in zone F are provided with air duct regulating valves in zone F for controlling the air volume of the air ducts; the DCS control module is connected to the fan M2 in zone F through the frequency converter in zone F, and is used to control the working frequency of the fan M2 in zone F; the DCS control module is respectively connected to each air duct regulating valve in zone F.

[0031] Its working principle is: the air duct of natural cold air is sent to the air inlet of fan M2 through a manual butterfly valve, the manual butterfly valve is in a normally open state, and the DCS controller can control the speed of fan M2 through the frequency converter to achieve air volume control. The air outlet of M2 is connected to the cooling air ducts corresponding to the upper and lower parts of the glass ribbon in zone F through the air duct, so that the glass ribbon can be air-cooled. An F zone air duct regulating valve is provided at each cooling air duct in zone F, and the DCS control module can control the regulating valve to achieve flow control.

[0032] The pneumatic valves corresponding to the air ducts in each zone of RET zone are respectively at the west plate (XV-RET-W), west middle plate (XV-RET-WM), middle plate (XV-RET-M), east middle plate (XV-RET-EM), east plate (XV-RET-E), and under the plate (XV-RET-DU). The pneumatic valves corresponding to the air ducts in F zone are respectively at the west plate (XV-FW), west middle plate (XV-F-WM), middle plate (XV-FM), east middle plate (XV-F-EM), east plate (XV-FE), and under the plate (XV-F-DU).

[0033] In this application, the regulating valve at the RET area air duct and the regulating valve at the F area air duct are both pneumatic regulating valves, and are controlled by the regulating signal sent by the DCS control module. The regulating valve at the RET area air duct and the regulating valve at the F area air duct are both equipped with local valve position display modules.

[0034] An air volume sensor is installed at the air inlet of the mixed air duct or the fan M2 in zone F to collect the actual air volume signal, and its output end is connected to the input end of the DCS control module. The DCS control module can control the rotation of the fan and the opening of the valve according to the detected air volume, thereby achieving more accurate control.

[0035] In this embodiment, the DCS control module is integrated into the DCS system of glass production control, and the purpose of centralized control is achieved by reusing the DCS system, while cost can be saved.

[0036] In this embodiment, the DCS control module is connected to the memory, and the memory is used to store event information corresponding to the cooling air control. The memory uses EEPROM to avoid data loss. In this embodiment, the wind control data and control data detected by the DCS system are stored in the EEPROM, which can realize data backup and traceability, and provide basic data for subsequent research and process improvement.

[0037] In a preferred embodiment of the present application, the DCS control module is connected to an alarm device for issuing an alarm for abnormalities in the cooling air control system of the annealing furnace. When the DCS control module detects that the temperature of the mixed air cannot meet the requirements or the detected air volume cannot meet the requirements, the alarm device simultaneously issues an alarm to indicate a fault, thereby avoiding the occurrence of product quality problems caused by air cooling that does not meet the requirements. The alarm device can use an audible and visual alarm device, a display screen, or a mobile terminal and other devices for remote notification of the alarm.

[0038] The utility model is a control system based on DCS centralized control of annealing furnace air valves. Each manual valve of the air valves in the RET zone and F zone of the photovoltaic glass annealing furnace is replaced by a pneumatic regulating valve controlled by DCS and forms a set of control logic, which is as follows:

[0039] like Figure 2 As shown, RET area (circulating hot air cooling area):

[0040] The hot air comes from the hot air extracted from the annealing furnace itself and mixed with natural cold air, which is extracted by the fan. The DCS signal (DCS-RETM-01) controls the fan frequency and adjusts the overall air volume. Figure 2 M is the motor of the fan. DCS intelligent pneumatic control valve control system configuration: The platinum resistance temperature measuring element and temperature measurement transmitter (TT-RETM-01) of the fan outlet duct feedback current signal based on the measured temperature, and compare it with the set value in the control room DCS control platform. When the difference between the two reaches a certain value, the DCS control platform sends a regulation signal to the pneumatic control valve (XV-RET-01). The actuator of the pneumatic control valve drives the valve stem with compressed air as the power source according to this signal, so that the valve stem drives the valve core to produce displacement, changing the natural cold air flow through the control valve until the test point temperature reaches 100%. The degree reaches the set value requirement, thereby achieving the purpose of automatically adjusting the hot air temperature; the pneumatic regulating valves of the air ducts in each zone on the upper and lower parts of the glass belt (taking the wide line as an example), the west plate (XV-RET-W), the west middle plate (XV-RET-WM), the middle plate (XV-RET-M), the east middle plate (XV-RET-EM), the east plate (XV-RET-E), and the lower plate (XV-RET-DU) are all controlled by the regulating signal sent by the DCS control platform to adjust the air volume of the air ducts in each zone. Each pneumatic regulating valve is equipped with a local valve position display (ZI).

[0041] like Figure 3 As shown, Zone F (cold air forced convection cooling zone):

[0042] In this area, the fan directly extracts natural cold air to forcefully cool the upper and lower surfaces of the glass belt. The manual butterfly valve (HV-F-01) on the air inlet pipe is in the normally open state, and the DCS signal (DCS-FM-01) controls the fan frequency to adjust the overall cooling air volume. The pneumatic regulating valves of the air ducts in each area of ​​the upper and lower parts of the glass belt (taking the wide line as an example), the west plate (XV-FW), the west middle plate (XV-F-WM), the middle plate (XV-FM), the east middle plate (XV-F-EM), the east plate (XV-FE), and the lower plate (XV-F-DU) are all controlled by the regulating signal sent by the DCS control platform to adjust the air volume of the air ducts in each area. Each pneumatic regulating valve is equipped with a local valve position display (ZI).

[0043] DCS has the ability to record events. It can record all events that occur in the system in chronological order, including all switch state changes, variable alarms, human-machine interface operations (such as parameter settings, control operations, etc.), equipment fault records, and software exception handling. The data is stored in the memory of the DCS system.

[0044] The utility model is a control system based on DCS centralized control of annealing kiln air valve, which has the following advantages and benefits:

[0045] 1. The pneumatic control valve is easy to operate. You only need to send a control signal to the pneumatic control valve on the DCS control platform to adjust the valve. The pneumatic control valve has high adjustment accuracy and is suitable for various media, including corrosive media and high-temperature and high-pressure media. At the same time, it saves manpower and ensures personnel safety.

[0046] 2. Pneumatic control valves can be remotely controlled and automatically controlled based on the DCS system to improve production efficiency, which is in line with the trend of industrial automation and intelligent development under the background of manufacturing industry upgrading.

[0047] 3. The integrity of the event record is the basis for analyzing and studying the performance of the product and the subsequent processing effects of the original glass (such as cold end cutting, tempering treatment, etc.), and provides a series of data support.

[0048] Obviously, the specific implementation of the present invention is not limited to the above-mentioned methods. As long as various non-substantial improvements are made using the method concept and technical solution of the present invention, they are all within the protection scope of the present invention.

Claims

1. An annealing kiln cooling air control system based on DCS centralized control, characterized in that: It includes a DCS control module, a RET zone fan M1, a natural cooling air control valve, a RET zone frequency converter, and a temperature measuring element, wherein the RET zone fan M1 is used to extract hot air from the annealing kiln, the RET zone fan M1 air outlet duct and the natural cooling air duct are both connected to a mixed air duct, the mixed air duct is used to mix the natural cooling air from the natural cooling air duct and the extracted hot air from the annealing kiln to obtain mixed air and connect it to each zone air duct at the upper and lower parts of the RET zone glass belt; each zone air duct at the upper and lower parts of the RET zone glass belt is provided with a RET zone air duct regulating valve; the temperature measuring element is used to detect the temperature data of the mixed air, and its output end is connected to the input end of the DCS control module; the output end of the DCS control module is connected to the RET zone fan M1 via the RET zone frequency converter, and is used to control the fan operating frequency of the RET zone fan M1; the DCS control module is respectively connected to the control ends of the natural cooling air control valve and the RET zone air duct regulating valve.

2. The annealing furnace cooling air control system based on DCS centralized control as claimed in claim 1, characterized in that: The control system also includes a fan M2 in zone F, a manual butterfly valve, and a frequency converter in zone F. The air inlet duct of natural cold air in zone F is connected to the air inlet of the fan M2 in zone F, and a manual butterfly valve is arranged on the air inlet duct; the air outlet of the fan M2 in zone F is respectively connected to the cooling air ducts corresponding to the upper and lower parts of the glass ribbon in zone F through air ducts, and the cooling air ducts corresponding to the upper and lower parts of the glass ribbon in zone F are provided with air duct regulating valves in zone F for controlling the air volume of the air ducts; the DCS control module is connected to the fan M2 in zone F through the frequency converter in zone F, and is used to control the working frequency of the fan M2 in zone F; the DCS control module is respectively connected to each air duct regulating valve in zone F.

3. The cooling air control system for an annealing kiln based on DCS centralized control as claimed in claim 1 or 2, characterized in that: The regulating valves at the RET zone air duct and the F zone air duct regulating valves are both pneumatic regulating valves, and are controlled by the regulating signals sent by the DCS control module.

4. The cooling air control system for an annealing furnace based on DCS centralized control as claimed in claim 3, characterized in that: The regulating valves at the RET zone air ducts and the regulating valves at the F zone air ducts are both equipped with local valve position display modules.

5. The cooling air control system for an annealing furnace based on DCS centralized control as claimed in claim 1 or 2, characterized in that: An air volume sensor is provided at the air inlet of the mixed air duct and / or the fan M2 in zone F for collecting actual air volume signals, and its output end is connected to the input end of the DCS control module.

6. The cooling air control system for an annealing furnace based on DCS centralized control as claimed in claim 1 or 2, characterized in that: The DCS control module is integrated into the DCS system for glass production control.

7. The cooling air control system for an annealing kiln based on DCS centralized control as claimed in claim 1 or 2, characterized in that: The DCS control module is connected to a memory, and the memory is used to store event information corresponding to cooling air control.

8. The cooling air control system for an annealing furnace based on DCS centralized control as claimed in claim 7, characterized in that: The memory adopts EEPROM.

9. The cooling air control system for an annealing furnace based on DCS centralized control as claimed in claim 1 or 2, characterized in that: The DCS control module is connected to an alarm device for issuing an alarm for abnormalities in the cooling air control system of the annealing furnace.

Images